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Geochronology and geochemistry of the Fangcheng Neoproterozoic alkali-syenites in East Qinling orogen and its geodynamic implications

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Chinese Science Bulletin 2008年第13期53卷 2050-2061页

作者： BAO ZhiWei WANG Qiang BAI GuoDian ZHAO ZhenHua SONG YaoWu liu xiaoming Key Laboratory for Metallogenic Dynamics Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China Key Laboratory of Isotope Geochronology and Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China Henan Institute of Geological Survey Zhengzhou 450007 China Key Laboratory of Continental Dynamics Department of Geology Northwest University Xi'an 710069 China

Finding of Neoproterozoic syenites at Fangcheng in the northern Qinling region of the East Qinling orogen provides an important constraint on timing of tectonic transformation to extensional regime. The alkaline pluton consists mainly of nepheline syenite,aegirine syenite,and alkali-feldspar syenite. The syenites are of intermediate (SiO2=54%―62%),rich in alkali (K2O+Na2O=12%―15%),aluminum (Al2O3=16.81%―23.26%) and large ion lithophile elements (LILE),without any obvious Nb,Ta,Zr,and Hf anoma-lies. The Fangcheng syenites are geochemically characterized by relative enrichment of LREE,minor differentiation of HREE,significant negative Eu anomalies (Eu=0.13―0.23),less negative εNd(t) values of -1.37 to -3.90,young Nd model ages of 1364 to 1569 Ma,and high zircon saturation temperatures of 915 to 1044℃. The syenitic magmas probably originated from small proportion melting of upper mantle in an extensional regime of intraplate-anorogenic tectonic setting,and have been slightly contaminated by crustal materials during ascending and/or emplacement. LA-ICP-MS zircon U-Pb dating yields ages of 844.3±1.6 Ma (MSWD=0.86),suggesting that the Fangcheng alkaline syenites formed in the early Neo-proterozoic. They are the oldest Neoproterozoic alkaline rocks ever recognized in the Qinling orogen as well as in South China. This implies that the tectonic regime of the Qinling region would have transformed from post-collisional stretch to intraplate-anorogenic extension no later than 844 Ma.

关键词：黑花岗石地球化学锆石测定年代

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Determination of U-Pb age and rare earth element concentrations of zircons from Cenozoic intrusions in northeastern China by laser ablation ICP-MS

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Chinese Science Bulletin 2003年第22期48卷 2411-2421页

作者： YUAN Honglin WU Fuyuan GAO Shan liu xiaoming XU Ping SUN Deyou Department of Geology Northwest University Xi' an 710069 China Institute of Geology and Geophysics Chinese Academy of SciencesBejing 100029 China Faculty of Earth Sciences China University of Geosciences Wuhan 430074 China College of Barth Sciences Jilin University hangchun 130061 China

Using the in situ zircon U-Pb dating method of LA-ICPMS, we analyzed the 31 Ma old SHRIMP U-Pb age of the Yongsheng nepheline syenite from southern Jilin Province under different spot sizes. The obtained ages are comparable with that of SHRIMP in both accuracy and precision. The age is also identical to that of the Yinmawanshan gabbro from the Liaodong Peninsula within error. Both the Yongsheng nepheline syenite and the Yinmawanshan gabbro represent the youngest known exposed intrusions in northeastern and even eastern China. The results indicate the Eocene mantle-derived magmatic underplating, and the rapid crustal uplifting of this region since 30 Ma. The analyses also document extremely high LREE concentrations and relatively flat REE patterns for the zircons from the Yongsheng nepheline syenite, which represent a new type of zircon REE pattern.

关键词： Pb 铅锆石中国东北地区地球年代学

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Hf isotopes of the 3.8 Ga zircons in eastern Hebei Province, China: Implications for early crustal evolution of the North China Craton

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Chinese Science Bulletin 2005年第21期50卷 2473-2480页

作者： WU Fuyuan YANG Jinhui liu xiaoming LI Tiesheng XIE Liewen YANG Yueheng tate Key Laboratory of Tectonic Evolution Institute of Geology and Geophysics Chinese Academy Of Sciences Beijing 100029 China Key Laboratory of Continental Dynamics Department of Geology Northwest University Xi'an 710069 China

Zircon U-Pb dating indicates that the fuchsite quartzite in eastern Hebei Province was derived from weathering and erosion of the 3.6-3.8 Ga granitic rocks. In-situ zircon Hf analyses show that the Lu-Hf isotopic system remained closed during later thermal disturbances. Zircons with concordant ages have Hf isotopic model ages of about 3.8 Ga, suggesting a recycling of this ancient crust. The ～3.8 Ga zircons have similar Hf isotopic compositions to those of chondrite, indicating that their source rocks (granitic rocks) were derived from partial melting of the juvenile crust which originated from a mantle without significant crust-mantle differentiation. Therefore, it is proposed that there was no large-scale crustal growth before ～3.8 Ga in eastern Hebei Province. Considering zircon Hf isotopic data from other areas, it is concluded that the most ancient crust in the North China Craton probably formed at about 4.0 Ga, and the possibility to find crust older than 4.0 Ga is very limited.

关键词：锆石同位素地壳进化中国地质构造

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The crucial roles of m^(6)A RNA modifications in cutaneous cancers:Implications in pathogenesis,metastasis,drug resistance,and targeted therapies

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Genes & Diseases 2023年第6期10卷 2320-2330页

作者： Cong Huang Kaoyuan Zhang Yang Guo Changbing Shen xiaoming liu Haiyan Huang Xia Dou Bo Yu Department of Dermatology Skin Research Institute of Peking University Shenzhen HospitalPeking University Shenzhen HospitalShenzhen Peking University-The Hong Kong University of Science and Technology Medical CenterShenzhenGuangdong 518036China Department of Dermatology Skin Research Institute of Peking University Shenzhen HospitalPeking University Shenzhen HospitalShenzhenGuangdong 518036China

N6-methyladenosine(m^(6)A)is the most abundant internal modification on *** is a dynamical and reversible process,which is regulated by m^(6)A methyltransferase and m^(6)A *** m^(6)A modified RNA can be specifically recognized by the m^(6)A reader,leading to RNA splicing,maturation,degradation or *** abnormality of m^(6)A RNA modification is closely related to a variety of biological processes,especially the occurrence and development of *** studies have shown that m^(6)A RNA modification is involved in the pathogenesis of skin ***,the precise molecular mechanisms of m^(6)A-mediated cutaneous tumorigenesis have not been fully ***,this review will summarize the biological characteristics of m^(6)A modification,its regulatory role and mechanism in skin cancers,and the recent research progress of m^(6)A-related molecular drugs,aiming to provide new ideas for clinical diagnosis and targeted therapy of cutaneous cancers.

关键词： Cutaneous squamous cell carcinoma Cutaneous melanoma m6A modification m^(6)A-related drugs Target Therapy

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NLoS Mitigation in ToA Localization Based on Spatial Correlation Filter and Iterative Minimum Residual

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China Communications 2012年第4期9卷 13-19页

作者： Luo Haiyong liu Shujing liu xiaoming Institute of Computing Technology Chinese Academy of Sciences Beijing 100191 P. R. China

To mitigate the Non-Line-of-Sight (NLoS) error which seriously affects the localization accuracy and robustness in complex indoor environment,a novel Iterative Minimum Residual (IMR) based on the consistency hypothesis of the residual and the error is proposed in this *** chooses the best subset of measurements to calculate the coordinates of the unknown node by comparing the residuals obtained with different subsets of *** reduce the time complexity of the IMR algorithm,Spatial Correlation Filter (SCF) is also proposed,which can remove the most serious NLoS distance with low calculation *** with the proposed SCF and IMR algorithm,nodes can be localized with high accuracy and low time *** results with real dataset demonstrate that the proposed algorithm can identify the NLoS range effectively with about 50% time cost of employing SCF only.

关键词： localization NLoS mitigation ToA iterativeminimum residual spatial correlation filter

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High-resolution gene mapping using admixture linkage disequilibrium

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Chinese Science Bulletin 2002年第20期47卷 1717-1719页

作者： TAO Shiheng CHU Jianhua liu xiaoming ZHANG Rongmei ZHANG Zhen LUO Zewei College of Life Science Northwest Sci.&Tech.University of Agriculture and ForestryYangling 712100China Laboratory of Population and Quantitative Genetics Institute of GeneticsSchool of Life ScienceFudan UniversityShanghai 200433China

This note reports simulation study on the rate of decay in linkage disequilibrium (LD) in mixed populations over multiple discrete generations and explores the usefulness of the LD analysis in high-resolution gene mapping. The results indicate that the smaller the recombination fraction and the fewer generations since admixture event, the higher power of the approach in gene mapping. The expected estimate of recombination fraction would give an estimate that is slightly biased upwards, if relevant genes are in tight linkage. The estimated recombination fraction is usually larger than the true value within 2-5 generations. From generations 10-20, the mean estimates are in good agreement with the true value. The method presented here enables estimation of means and corresponding confidence intervals of the recombination fraction at any number of generations.

关键词： gene mapping computer simulation model admixture finite populations.

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U-Pb dating of detrital zircons from the Wudangshan Group in the South Qinling and its geological significance

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Chinese Science Bulletin 2010年第22期55卷 2440-2448页

作者： LING WenLi DUAN RuiChun liu xiaoming CHENG JianPing MAO XinWu PENG LianHong liu ZaoXue YANG HongMei REN BangFang Faculty of Earth Sciences China University of Geosciences Wuhan 430074 China State Key Laboratory of Geological Process and Mineral Resources China University of Geosciences Wuhan 430074 China Yichang Institute of Geology and Mineral Resources Yichang 443003 China State Key Laboratory of Continental Geodynamics Northwest University Xi'an 710069 China Geological Survey of Hubei Province Wuhan 430022 China Tianjin Institute of Geology and Mineral Resources Tianjin 300170 China

U-Pb dating was made by the LA-ICP-MS method for detrital zircons from the Wudangshan volcanic-sedimentary succession in the South Qinling. Samples comprise quartz sandstones of the Wudangshan Group collected from the base of the Yangping For-mation and an upper layer of the Shuangtai Formation overlain its volcanic sequence, and two river-sand collections from the drainage systems cutting across the two formations, respectively. The results show that the Yangping detrital zircons are domi-nated by 830–780 Ma grains with a minor population of ～1.0–0.84 Ga and sporadic grains of ～2.6, ～2.4 and 2.0 Ga, whereas the Shuangtai zircons yield an upper intercept age of 763±33 Ma, identical to the timing of the Wudangshan volcanism within error, with few concordant grains of 1.9 and 0.86 Ga. Age spectra for the two river-sand samples are similar to those of the Yangping and Shuangtai Formations, respectively. It thus suggests that the Wudangshan strata are less than 780 Ma, whereas their major detrital zircon populations of 1.0–0.85 Ga and 830–780 Ma are consistent with timing of the Hannan magmatic activities along the northwestern margin of the South China Block. This suggests a Hannan or adjacent area provenance for the Wudangshan strata. The Wudang area is characterized by rift-related igneous events at ～755 and ～680 Ma, respectively, pointing to a tectono-magmatic history different from the Hannan area. It is inferred that the ～755 Ma magmatism is likely to indicate a separation of the South China Block from the supercontinent Rodinia, while the ～680 Ma event suggests a further split between the South Qinling and some unknown continent.

关键词：碎屑锆石武当山南秦岭地质意义 Pb 岩浆活动石英砂岩火山沉积

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Timing of the Wudangshan, Yaolinghe volcanic sequences and mafic sills in South Qinling: U-Pb zircon geochronology and tectonic implication

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Chinese Science Bulletin 2008年第14期53卷 2192-2199页

作者： LING WenLi REN BangFang DUAN RuiChun liu xiaoming MAO XinWu PENG LianHong liu ZaoXue CHENG JianPing YANG HongMei Faculty of Earth Sciences China University of Geosciences Wuhan 430074 China State Key Laboratory of Geological Process and Mineral Resources China University of Geosciences Wuhan 430074 China State Key Laboratory of Continental Geodynamics Northwest University Xi'an 710069 China Geological Survey of Hubei Province Wuhan 430022 China

The Wudangshan, Yaolinghe volcanic-sedimentary sequences and doleritic-gabbroic sills comprise the largest exposed Precambrian basement in South Qinling. Zircons separated from 5 volcanic-pyroclas- tic samples of the Wudangshan Group, 2 volcanic samples of the Yaolinghe Group and one sample for the mafic sills were used for U-Pb dating by laser ablation-inductively coupled plasma mass spec- trometry (LA-ICPMS). The results reveal that the Wudangshan volcanic sequence was formed at (755±3) Ma (a weighted mean from the 5 samples, MSWD=0.47), whereas the Yaolinghe volcanic suite and the mafic sill were crystallized at (685±5) (2 samples, MSWD=0.36) and (679±3) Ma (MSWD=1.6), respectively, which are equal to each other within analysis errors. These ages are markedly younger than those previously documented for the rocks. The newly obtained ages for the Wudangshan and Yaolinghe Groups are identical to those of the bottom Liantuo and slightly older than those of the Nantuo Forma- tions, respectively, lower strata of the Nanhua (middle to late Neoproterozoic) stratotype section in eastern Three Gorges, Yangtze craton. A range of inherited magmatic zircons was recognized with ages of 830 to 780 Ma, which are typical of Neoprotzrozoic magmatisms recorded along the margins and interior of the Yangtze craton. Thus, there is Neoproterozoic basement comprising 830―780 Ma igne- ous suites in South Qinling; the inherited zircons were detrital sediments derived from the northern margin of the Yangtze craton. Accordingly, it is suggested that the South Qinling is a segment of the Yangtze craton before the Qinling Orogeny.

关键词：武当山铁镁质岩床地质年代地质学

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Chemotherapy-induced small extracellular vesicles prime the pre-metastatic niche to accelerate neuroblastoma metastasis

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Genes & Diseases 2024年第4期11卷 65-68页

作者： Carson A.Wills xiaoming liu Longgui Chen Yuanjun Zhao Zhenqiu liu Vladimir S.Spiegelman Jeffrey Sundstrom Hong-Gang Wang Department of Pediatrics Division of Pediatric Hematology and OncologyThe Pennsylvania State University Collegeof MedicinePA 17033USA Department of Ophthalmology The Pennsylvania State University College of MedicinePA 17033USA Department of Public Health Sciences The Pennsylvania StateUniversityCollegeofMedicinePA 17033USA

Neuroblastoma is the most common extracranial solid tumor in children,accounting for more than 10%of cancerrelated deaths in this *** standard of care for patients diagnosed with medium-to high-risk neuroblastoma,incl... 详细信息

关键词： neuroblastoma metastatic metastasis

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Optimizing the grain size and grain boundary morphology of (K,Na) NbO_(3)-based ceramics: Paving the way for ultrahigh energy storage capacitors

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Journal of Materiomics 2021年第4期7卷 780-789页

作者： Xiaozhi Wang Yu Huan Peiyao Zhao xiaoming liu Tao Wei Qiwen Zhang Xiaohui Wang School of Material Science and Engineering University of JinanJinan250022China State Key Laboratory of New Ceramics and Fine Processing School of Materials Science and EngineeringTsinghua UniversityBeijing100084China Key Laboratory of Electromagnetic Processing of Materials(Ministry of Education) Northeastern UniversityShenyang110819China The Chinese Ceramic Society Beijing100831China

Relaxor dielectric ceramic capacitors are very attractive for high-power energy ***,the low breakdown strength severely restricts improvements to the energy storage density and practical ***,a strategy of designing small grain sizes and abundant amorphous grain boundaries is proposed to improve the energy storage properties under the guidance of phase field theory.0.925(K_(0.5)Na_(0.5))NbO_(3)-e0.075Bi(Zn_(2/3)(Ta_(0.5)Nb_(0.5))1/3)O_(3)(KNNe-BZTN)relaxor ferroelectric ceramic is taken as an example to verify our *** grain sizes and grain boundaries of the KNNeBZTN ceramics are carefully controlled by the high-energy ball milling method and twoestep sintering *** analysis and diffusion reflectance spectra demonstrate that KNNeBZTN ceramics with a small grain size and abundant amorphous grain boundary exhibit a lower charge carrier concentration and higher band *** a consequence,the breakdown electric field of KNNeBZTN ceramics increases from 222 kV/cm to 317 kV/cm when the grain size is decreased from 410 nm to 200 nm,accompanied by a slightly degraded maximum *** ceramics with an average grain size of~250 nm and abundant amorphous grain boundaries exhibit optimum energy storage properties with a high recoverable energy density of 4.02 J/cm^(3) and a high energy efficiency of 87.4%.This successful local structural design opens up a new paradigm to improve the energy storage performance of other dielectric ceramic capacitors for electrical energy storage.

关键词： Grain size Grain boundary KNN-based dielectric ceramic capacitors Energy storage properties Breakdown strength Two-step sintering strategy

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